Pigment and paint



UNITED STATES PATENT OFFICE.

LOUIS'E. BARTON, OF NIAGARA FALLS, YORK, ASSIGN'OR TO THE TITANIUM ALLOY MANUFACTURING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

I'IGMENT AND PAINT.

1,313,874. Specification of Letters Patent.

No Drawing.

To all whom it may concern:

Be it known that I, LoUIs E. BARTON, a citizen of the United States, and a resident of Niagara Falls, in the county of Niagara and State of New York, have invented certain new and useful Improvements in Pi for which Letters Patent No. 1,155,462 were granted me October 5th, 1915; and the obects of my present invention comprise provision of procedures and means whereby in certain respects paints containing such composite pigments may, for certain uses, and under certain conditions, be im roved. The enormous extent of natural eposits of titanic oxid being long known, it has accordingly been sought, though unsuccessfully, to'make use of that compound as a pigment in paints as, for example, either in the form of natural rutile, or combined with iron oxids in colored pigments.

The dilii'cult and expense of industrially separating sue titanic oxid in required purity and quantity from undesired substances therewith intermingled in nature, such as iron and gangue, have long prohibited such use of titanic oxid in aint. Notwithstanding the comparatively recent advent of cheaper and better methods of concentration, the titanic oxid products of the earlier of these failed, in paints, for various reasons, including their crystalline and too gritty character and comparative inability to impart to paint the unsurpassed hiding owers since developed by aid of titanic ox1d. It is only .quite recently that methods have been invented resulting in purer' concentrates, the titanic oxid (TiO of which is in amor hous state and chemically uncombined with other substances, such methods being those, for instance, claimed in Letters Patent Nos. 1,106,406, 1,106,407, 1,106,108,1,106,409 and 1,106,410, anted to Auguste J. Rossi and myself on ugust 14, 1914. While such last mentioned titanic oxid concentrates are very useful for many purposes, including pigments 1n paints, their hiding power in the latter has been surpassed by the above referred tocomposite Application filed March 21, 1916. Serial No. 85,561.

titanic oxid pigments, the which are, as per the claims of said Patent No. 1,155,462, distinguished from prior products as compris- 1ng titanic oxid and a sulfate, or these and also a comparatively negligible but usually undesired modicum of iron oxid, or, more generally speaking, as consisting essentially of carrier particles consisting of a sulfate base, or extender, having thereto-adhering, or therewith coalesced, smaller particles of titanic oxid, and one of my methods for producing which as by precipitation, etc., are set forth in the said last mentioned Letters Patent.

My researches, and experiments on industrial scales, have, however, resulted in demonstratin that, notwithstandin that much greater hlding power is imparta le to paints y my said composite titanic oxid pigments as compared with any other forms of titanic oxid, or other titanic oxid pigments, or any other pigments such as white lead or zinc oxid, known to me; and notwithstanding the many other superior properties of my said composite pigments for the purpose, they cannot, in some instances, be employed as the sole, or preponderating, pigment constituent of alnts without development of faults in fina l results which are, more or less, undesirable, if not sometimes prohibitory.

For example, such paints prepared, spread and dried in the usual manner, have, 1n too many instances, been found to retain too long, if not indefinitely, a sticky or, as termed in the art a tacky exterior film by which were caught,.and to which adhered,

with consequent soiling or discoloration of the paint surface. On the other hand, some of such paints, after ex osure to the air so long as to become comp etely hardened, began to disintegrate, or, as it 1s termed in the art, chalk, on the surface, the rubbing of which, as by usual cleansing or other wear, removed such disintegrated portions, exposing underlyin particles to similar disintegration, by w ich the coat of paint might be undesirably reduced in thickness or ultimately altogether removed.

I have discovered that the above-mentioned difiiculties and faults, and others, can be overcome by thoroughly mixing with my said composite titanic oxid pigments a relatively small quantity of the oxid of some metal other than titanium, preferably the oxid of zinc '(ZnO) or other non-ferruginous oxid. y 7

Such additions to myv composite titanic oxid pigments can be made at any time in any convenient manner, but I find that the bestresults are attained by, as intimately and homogeneously as possible, mixing the oxid of the metal other than titanium with such composite titanic oxid pigment, prior to being worked up for paint with the usual vehicles, and to this end I first thoroughly grind together said composite pigment and oxid, preferably in their dry state, after which they are still more intimately mixed by the usual grinding, together with oil, to bring the product into the paste form in which paint is usually marketed preparatory to its being further manipulated into condi tion suitable for immediate use, as by the customary further incorporation of said vehicles, such as oils, driers, thinners, or varnish, etc. though unpreferably, be incorporated by mixing or grinding together preliminarily, separately prepared pastes, the one containing it, and the other the composite titanic oxid pigments, or it may even be introduced during the final reduction with said vehicles of the paint containing the composite titanic oxid pigment.

The proportions of the oxid of the metal other than titanium so added to my composite titanic oxid pigments for the purposes specified should, in each case, be determined upon consideration of the conditions under which the paint is to be finally used.

Thus, for example, to prevent chalking, if the paint is to be exposed to sunlight and weather, as .in out-of-doors painting, the addition of zinc oxid should be as much as from 15% to 25% calculated on thecombination thereof with my composite titanic oxid pigment, while for interior painting from 15% to 5%, or sometimes even less. I find to be sufiicient. As preventing tackiness, an addition of 5% to 10% of zinc oxid gives excellent results if the paint is spread under favorable drying conditions, as in average summer weather. In exceptionally warm. dry, weather, even such small amounts as 2% to ,5% are efficient, but in cool, damp weather, as in early spring, or

The added oxid, may, however, I

Wood than on metal, such as structural steel,

for example.

Those skilled in the paint art will readily determine the proportions best suited to each particular case, the rule being to restrict the addition to as little as compatible with attainment of its aforesaid specific beneficial effects, since in other respects, while increasing cost, it is of little value, or even sometimes deterimental to obtaining the distinguishing hiding power or other beneficial characteristics, in paint, which are peculiarly attributable to my said composite titanic oxid pigments, and it will be under stood that by, as above, mentioning the proportions which I have, in certain cases,

found most effective, I do not thereby, nor 7 thereto, limit my invention.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is the following:

1. Paint containing a i titanic oxid and-an 1n'so l u with oxid of zinc. 1

2. Asa new article a composite pigment 1e sulfate mixe gment comprisin comprising titanic oxid and an insoluble sulfate mixed withoxid of zinc.

3. As a new article a composite pigment comprising particles of an insoluble sulfate base and thereto-adhering smaller particles of titanic oxid mixed with zinc oxid.

4. Paint containing oxid of zinc and also a pigment comprising insoluble carrier par.-

ticles having therewith coalesced and there- 100 to adherent particles of titanic oxid.

LOUIS E. BARTON;

Witnesses:

B. O. POITER, ROBERT P. EASTON. 

